The implementation of peak-valley time-of-use power price will lead to power load adjustment to affect power grid planning. In order to slove the problem

a power grid planning mtehod considering the influence of peak-valley time-of-use power price is proposed. A peak-valley time-of-use power price model based on the cost-benefit analysis involving each participant in demand side management(DSM)is developed

as is substation capacity planning model. Where the ratio of the peak price to valley price is stable

the optimal pull-apart rate of peak-valley time-of-use power price in the example area is selected according to the calculation results of the peak-valley time-of-use power price model. Thus the modified scheme considering the influence of peak-valley time-of-use power price is compared with the conventional substation capacity planning scheme. It is concluded that the modified scheme can still satisfy the load-balance of the example area although the new substation capacity is reduced. The scheme can also make each participant in DSM get more profits

because it will save the construction investment and the power consumption cost of consumers. The economic benefits and rationality will appreciably be enhanced.